This invention relates to a porous composite material having a hydrophilic polymer layer provided over the interior surface of each of the pores of a porous hydrophobic polymer body.
It is well known that a foaming treatment of a mixture containing a resin such as polyethylene and a foaming agent may produce a porous material. The heat-insulating and sound-proofing properties of such porous material have led to use of the material as construction materials. However, the conventional porous material has a defect that it is poor in hydrophilic or hygroscopic property.